JPH11144214A - Device for inspecting touch of magnetic tape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for inspecting the touch of a magnetic tape capable of accurately and quantatively grasping the relation of the touched width of magnetic tape and the tape angle with the projected amount of the magnetic head. SOLUTION: This device for inspecting the touch of magnetic tape is provided with a magnetic head mounting jig 3 for positionally fixing the fixed magnetic head 4 and a touching state detecting means for measuring both of the touched width of magnetic tape against the fixed magnetic head 4 and the approach angle of magnetic tape against the fixed magnetic head 4. The touched width is measured, e.g. in such a manner that a cartridge wound round with a light transparent tape is mounted and brought into contact with the fixed magnetic head 4 to observe interference fringes by an optical microscope 11 from the rear side of the light transparent tape. Also, the tape angle is measured by observing the edge of the light transparent tape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic tape hit inspection apparatus capable of accurately evaluating a hit state of a magnetic tape against a fixed magnetic head.

[0002]

2. Description of the Related Art For example, when a fixed magnetic head is mounted on a recording / reproducing apparatus or the like, it is necessary to make the amount of protrusion appropriate and to make the state of contact with the magnetic tape good.

In particular, in a magnetic head adapted for high-density recording, the contact state of the magnetic tape greatly affects the electromagnetic conversion characteristics. If the contact is poor, satisfactory recording, reproduction and erasing become impossible.

On the other hand, when evaluating the electromagnetic conversion characteristics of the fixed magnetic head, it is necessary to evaluate the characteristics while keeping the contact state of the magnetic tape constant. In any case, the contact width of the magnetic tape, the tape angle, and the like are required. Techniques for quantitative measurement are indispensable.

Heretofore, little attention has been paid to the inspection of the contact state of the magnetic tape, and only a method using ink has been known.

According to this ink-based method, a quick-drying oil-based ink (so-called magic ink) is previously applied to the surface of a magnetic head (a sliding surface of a magnetic recording medium), and the magnetic tape is actually brought into contact with the ink to remove the ink. It is to find the width of the part. When the magnetic tape is brought into contact with the magnetic head, the ink is rubbed off only at the part where the magnetic tape and the magnetic head surface are in direct contact. It will be done.

[0007]

However, in this method using ink, even a slight contact can cause the ink to fall off, and it is difficult to accurately evaluate the ink due to accidental contact with a magnetic tape or the like.

Further, when the relationship between the protrusion amount of the magnetic head and the tape angle is reached, actual data cannot be obtained.
There is a situation where it has to be obtained by calculation from the head dimensions, the magnetic tape width, and the like.

When considering the actual contact with the magnetic tape,
The value obtained by the calculation does not always match the actually measured value, and therefore, the above method cannot accurately grasp the relationship between the hit dimension (hit width, tape angle) and the head characteristics.

The present invention has been proposed in view of such a conventional situation, and accurately and quantitatively grasps the relationship between the protrusion amount of a magnetic head, the width per magnetic tape, and the tape angle. It is an object of the present invention to provide a magnetic tape hit inspection apparatus capable of performing the following.

[0011]

In order to achieve the above-mentioned object, a magnetic tape hit detecting apparatus according to the present invention comprises: a magnetic head mounting jig for positioning and fixing a fixed magnetic head; It has a hit state detecting means for measuring both the width and the angle (tape angle) of the magnetic tape entering the fixed magnetic head.

In the inspection apparatus of the present invention, since the hit width of the magnetic tape and the tape angle are actually measured, the relationship between the hit width, the tape angle, the head protrusion amount, and the head characteristics can be grasped accurately and quantitatively.

In the above-mentioned hit inspection device, a cartridge having a light-transmitting tape wound thereon is mounted, the light-transmitting tape is brought into contact with a fixed magnetic head, and interference fringes are observed from the back side by an optical microscope. If the hitting width is measured by the method, the hitting width is measured much more accurately than the conventional method, and the reliability of the measurement is significantly improved.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of a magnetic tape hit inspection apparatus to which the present invention is applied will be described below with reference to the drawings.

FIG. 1 shows an example of a dual-purpose device capable of evaluating the characteristics of a magnetic head and inspecting a magnetic tape with a single device.

This dual-purpose device is obtained by incorporating a cartridge fixing jig 2 for mounting a magnetic tape cartridge and a magnetic head fixing jig 3 into an apparatus main body 1. A magnetic head 4 is attached to the tip of the magnetic head fixing jig 3. By mounting and mounting the magnetic tape cartridge 5 on the cartridge fixing jig 2, recording and reproduction are performed on the magnetic tape 6, and the electromagnetic conversion characteristics of the magnetic head 4 are evaluated, similarly to a normal recording and reproducing apparatus. Is possible.

Here, the magnetic head fixing jig 3 can be moved in the direction of arrow A in the figure, and by adjusting this, the magnetic head 4 is moved forward or backward with respect to the magnetic tape 6 so that the protrusion amount is increased. Can be adjusted.

The cartridge fixing jig 2 is provided with a tape drive mechanism including a drive motor 7, a drive belt 8, guide rolls 9, 10, and the like. Magnetic tape 6
Is driven by this drive mechanism.

In addition to the cartridge fixing jig 2 and the magnetic head fixing jig 3, the optical microscope 11 includes an optical microscope 11 as a means for detecting the contact width of the magnetic tape 6 with the magnetic head 4 and the tape angle. It is attached to the position corresponding to 4.

The optical microscope 11 is attached to the distal end 12a of the support plate 12 and is disposed above the magnetic head 4. The base end 12b of the support plate 12 is
Attached to.

The microscope operating jig 13 is movable in three-dimensional directions, specifically, in the X direction and the Y direction in the drawing, and in the Z direction perpendicular to the paper surface. It is also rotatable about the shaft 14 in the θ direction in the figure around the center of rotation.

Therefore, by individually adjusting the adjustment knobs 13a to 13e of the microscope operating jig 13, the optical microscope 11 attached to the tip of the support plate 12 can be arranged at an arbitrary position.

The hit width and tape angle are actually measured using the optical microscope 11. When measuring the hit width, a transparent or translucent tape is used, and the hit width is observed through the tape.

FIG. 2 shows an example of a cartridge used for measurement. The cartridge 15 has the same size and structure as a normal magnetic tape cartridge, but the tape wound around the reels 16 and 17 and accommodated therein is
It is a transparent or translucent light transmissive tape 18.

A part of the front surface of the cartridge 15 is recessed to form a recess 15a.
In this case, the light transmissive tape 18 is run facing the outside. Therefore, the magnetic head 4 is also protruded to a position opposed to the concave portion 15a and comes into contact with the light transmissive tape 18.

The magnetic head 4 is provided in the recess 15a.
Plate (mirror) 1 on the back side of light transmissive tape 18
9 are installed. The mirror 19 is mounted obliquely at an angle of inclination of approximately 45 °, so that when the mirror 19 is viewed from above, the light transmissive tape 18 in contact with the magnetic head 4 is shown.

Next, the measurement of the contact width and the measurement of the tape angle by the above apparatus will be described.

First, in order to measure the contact width, the cartridge 15 having the light transmitting tape 18 shown in FIG.

Then, the magnetic head fixing jig 3 is adjusted so that the magnetic head 4 is protruded and is brought into contact with the light transmissive tape 18.

In this state, the optical microscope 11 is moved to a position above the mirror 19 provided on the cartridge 15, and the contact portion of the magnetic head 4 with the light-transmitting tape 18 is observed from the back side through the mirror 19. .

FIG. 3 schematically shows this observation image. In the area where the light transmissive tape 18 and the magnetic head 4 are in contact (the contact width area), light is reflected and looks bright. On the other hand, the light transmissive tape 18 is
In a region away from the contact area (outside the contact width region), interference occurs due to a difference in the optical path of the reflected light due to a change in the interval between the magnetic head 4 and the light transmissive tape 18, and interference fringes are observed.

Therefore, by measuring the distance from the magnetic gap g of the magnetic head 4 to the innermost interference fringe J by using the scales in the field of view of the optical microscope 11,
Each of the contact widths T ₁ and T ₂ on both sides of the magnetic gap g,
The overall hit width T can be measured.

On the other hand, the tape angle is measured by observing the edge of the light transmitting tape 18 (or the magnetic tape 6).

That is, first, the optical microscope 11 is moved, and the edge of the light transmissive tape 18 is observed with the optical microscope 11 in a state where the magnetic head 4 is not in contact, and the horizontal cursor H in the visual field is adjusted to this. Next, the magnetic head 4 is brought into contact. Then, as shown in FIG. 4, the light transmissive tape 18 has a predetermined tape angle according to the amount of protrusion of the magnetic head 4. This tape angle α
Can be measured as the inclination angle with respect to the horizontal cursor H, and can be easily calculated, for example, by reading the scale of the horizontal cursor H and the scale of the vertical cursor V at the position where the light transmissive tapes intersect.

The details of the measurement of the contact width and the tape angle have been described above. The apparatus of this embodiment can also measure the electromagnetic conversion characteristics of the magnetic head. The relationship between the contact dimension between the head and the magnetic tape and the head characteristics can be grasped.

Actually, these relationships were examined using the same apparatus as described above. The fixed magnetic head used for the evaluation is a fixed magnetic head for a data cartridge. As shown in FIG. 4, a reproducing head W is disposed on both sides of the recording head R in the direction in which the magnetic tape runs, and an erasing head is further disposed outside the reproducing head W. E
Is arranged.

The measurement was performed on the erase head E among the heads constituting the fixed magnetic head.

As the measuring device, a head characteristic evaluation device is diverted here, and an optical microscope and a microscope operating jig are attached thereto, and the evaluation of the characteristics of the magnetic head and the inspection of the magnetic tape can be performed by one device. The device.

First, a cartridge incorporating a light-transmitting tape as shown in FIG.
The fixed magnetic head was protruded toward the light transmissive tape and was brought into contact therewith. The measurement was performed while changing the protrusion amount, and the value at each protrusion amount was measured. The amount of protrusion of the fixed magnetic head was read from a micrometer of a jig for fixing the magnetic head.

Here, the tape angle and the hitting width were measured, and these measuring methods are as described above. That is, the measurement of the tape angle is performed by observing the edge of the light transmitting tape with an optical microscope,
Microscopic readings were read and calculated. Also,
The hit width was measured by observing interference fringes due to the optical path difference of the reflected light on the contact surface between the light transmitting tape and the fixed magnetic head.

After the magnetic tape contact inspection was completed as described above, the cartridge incorporating the light transmitting tape was replaced with a magnetic tape cartridge, and the head characteristics were measured.

The measurement was repeated while changing the amount of protrusion of the fixed magnetic head. Table 1 shows the results.

[0043]

[Table 1]

By performing the measurement using the above-described apparatus, the relationship between the contact dimension of the fixed magnetic head and the magnetic tape and the head characteristics could be quantitatively clearly and simply expressed.

[0045]

As is clear from the above description, according to the present invention, it is possible to accurately and quantitatively measure the relationship between the protrusion amount of the magnetic head, the width per magnetic tape, and the tape angle. is there.

Therefore, for example, it is possible to quantitatively evaluate the relationship between the magnetic head characteristics and the dimension per magnetic tape.

[Brief description of the drawings]

FIG. 1 is a schematic plan view showing one configuration example of a magnetic tape hit inspection apparatus to which the present invention is applied.

FIG. 2 is a schematic perspective view showing an example of a light transmissive tape cartridge.

FIG. 3 is a schematic plan view schematically showing an observation image of a contact portion between a magnetic head and a light transmitting tape.

FIG. 4 is a schematic diagram showing a method of measuring a tape angle.

[Explanation of symbols]

3 magnetic head fixing jig, 4 magnetic head, 11 optical microscope, 15 cartridge, 18 light transmissive tape,
19 mirror (reflector)

Claims (5)

[Claims] A magnetic head mounting jig for positioning and fixing a fixed magnetic head; a hit state detecting means for measuring both a contact width of a magnetic tape with respect to the fixed magnetic head and an angle of approach of the magnetic tape to the fixed magnetic head; A magnetic tape hit inspection device, characterized by having: 2. A light-transmitting tape comprising a cartridge wound thereon, wherein the light-transmitting tape is brought into contact with a fixed magnetic head, and interference fringes are observed by an optical microscope from the back side of the light-transmitting tape. The magnetic tape hit inspection device according to claim 1, wherein the hit width is measured by: 3. The magnetic tape hit inspection device according to claim 2, wherein the cartridge is provided with a reflection plate obliquely at a position on the back surface side of the light transmissive tape. 4. The inspection apparatus according to claim 2, wherein the optical microscope is mounted on a microscope operating jig having a three-dimensional position adjusting means and a tilt adjusting means. 5. The magnetic tape hit inspection apparatus according to claim 1, further comprising a characteristic evaluation means for measuring an electromagnetic conversion characteristic of the fixed magnetic head.